/ Dictionary / Index P plio-: Meaning and Definition of Find definitions for: plio- Pronunciation: [key] var. of Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Pliny Pliocene Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language